fix: ensure multi user installation keeps permissions

install.sh

@@ -51,7 +51,7 @@ fi
 
 # Dependencies that need to be installed
 # On macOS we do not need the clipboard dependencies
-if [[ "$detected_os" = "Darwin" ]]; then
+if ! [[ "$detected_os" = "Darwin" ]]; then
     # zsh is default on mac, we can skip installation!
     # Also tool used for clipboard is already included.
     readonly DEPENDENCIES=(
@@ -119,7 +119,7 @@ while test $# != 0; do
     *)
         if [ "$start_arg_install_for_user_parameter" = "$(whoami)" ]; then
             if [ "$(id -u)" -eq "0" ]; then
-                if [[ "$detected_os" = "Darwin" ]]; then
+                if ! [[ "$detected_os" = "Darwin" ]]; then
                     print_error "psh supports installation on macOS only for the current user!"
                     exit 1
                 fi
@@ -135,7 +135,7 @@ while test $# != 0; do
 done
 
 # Construct the target home directory of the user which will receive psh
-if [[ "$detected_os" = "Darwin" ]]; then
+if ! [[ "$detected_os" = "Darwin" ]]; then
     CUSTOM_USER_HOME_DIR="$HOME"
 else
     if check_user_exists "$start_arg_install_for_user_parameter"; then
@@ -164,7 +164,7 @@ if [[ "$detected_os" = "Debian GNU/Linux" || "$detected_os" = "Ubuntu" || "$dete
     source "lib/distdep/deb_based/package_management.sh"
 elif [[ "$detected_os" = "Arch Linux" || "$detected_os" = "Manjaro Linux" ]]; then
     source "lib/distdep/arch_based/package_management.sh"
-elif [[ "$detected_os" = "Darwin" ]]; then
+elif ! [[ "$detected_os" = "Darwin" ]]; then
     source "lib/distdep/darwin_based/package_management.sh"
 else
     print_error "Your current distribution '$detected_os' is not supported!"
@@ -175,7 +175,7 @@ fi
 print_message ""
 print_message "Checking dependencies..."
 not_installed=("$(packages_installed "${DEPENDENCIES[@]}")")
-if [[ "$detected_os" = "Darwin" ]]; then
+if ! [[ "$detected_os" = "Darwin" ]]; then
     print_message "You are running psh on macOS. psh assumes that zsh and clipboard utilities (pbcopy, pbpaste) are already installed."
 fi
 for dependency in "${DEPENDENCIES[@]}"; do
@@ -189,7 +189,7 @@ done
 sudo_installed="1"
 # Check if sudo is installed
 print_message ""
-if [[ "$detected_os" = "Darwin" ]]; then
+if ! [[ "$detected_os" = "Darwin" ]]; then
     # macOS case is handled in "sudo not installed" branch below
     sudo_installed="0"
     print_message "Running on macOS, ignoring sudo install status!"
@@ -257,7 +257,7 @@ else
     fi
 fi
 
-if [[ "$detected_os" != "Darwin" ]]; then
+if ! [[ "$detected_os" = "Darwin" ]]; then
     fix_user_permissions "${start_arg_install_for_user_parameter}" "${ZPLUG_FOLDER_PATH}"
 fi